1. Field of the Invention
The present invention relates to a power supply system for supplying power to loads, and a fuel cell unit. More particularly, the present invention relates to a power supply system having a fuel cell.
2. Description of the Related Art
Conventionally, a solar power generation, a fuel cell, etc. have been considered to be an auxiliary power source of an electric power system in each house. In addition, the increase of power demand in recent years will cause a shortage of power supply from the electric power system in the near future. For this reason, power supply to each house will be heavily dependent on a solar power generation, a fuel cell, etc. In other words, it is expected that a fuel cell and on the like will be employed as an auxiliary power source in the past function as a main power source in each house.
However, electric power generation of the fuel cell installed in each house is limited compared with the electric power generation of the electric power system. Therefore, supply shortage caused by higher demand capability than electric power generation of the fuel cell in each house may increase compared with the power supply from the current electric power system. In this case, it is not preferable to break the power supply to all loads by a breaker as the current power supplying method from the current electric power system because the frequency of supply shortage increases. In addition, it is necessary to install a high capacity fuel cell to prevent supply shortage. However, it is not preferable in economical efficiency.